With the continuous enhancement of human environmental awareness, environmental protection laws and regulations are also being introduced and improved. All industries are working together in the direction of environmental protection, green, healthy.With the development of flexible packaging industry, it has become an inevitable trend to reduce and remove the organic solvents used in the compound.Water-based composite adhesive in the use of methods and price technology and other aspects are gradually mature, become the new darling of the soft bag industry, has achieved rapid development at home and abroad. In plastic composite and plastic aluminum composite, water - based polyurethane and acrylic polymers are mainly used. Water-based adhesive mainly has the following (1)High composite strength. The molecular weight of water-based adhesive is large, which is dozens of times that of polyurethane adhesive. Its bonding force is mainly based on van der Waals force, which belongs to physical adsorption, so a very small amount of adhesive can achieve quite high composite strength. (2)soft, more suitable for the compound of aluminum plating film. One-component water-based adhesives are softer than two-component polyurethane adhesives. When they fully set, polyurethane adhesives are very rigid, while water-based adhesives are very soft. Therefore, the soft properties and elasticity of water-based adhesive are more suitable for the composite of aluminum plating film, which does not easily lead to the transfer of aluminum plating film. (3)No need to mature, off the machine can be sliced. Single component water-based adhesive compound does not need curing, after off the machine can be splayed, bag making and other subsequent processes. This is because of the high initial adhesive strength, especially shear strength, to ensure that the product in the composite and cutting process will not produce "tunnel", fold and other problems. Moreover, the use of water-based adhesive composite film in 4 hours after placement, strength can improve by 50%. Here is not the concept of maturation, the colloid itself did not occur crosslinking, mainly with the leveling of the glue, composite strength also improved. (4)Thin adhesive layer, good transparency. Due to the small amount of water-based adhesive, and the concentration of adhesive is higher than that of solvent-based adhesive, so the need for drying and discharge of water is far less than solvent-based adhesive. After the moisture is completely dried, the film will become very transparent, because the adhesive layer is thinner, so the transparency of the composite is better than that of the solvent adhesive. (5)Environmental protection, harmless to people. There is no solvent residue after drying of water-based adhesive, many manufacturers use water-based adhesive to avoid residual solvent compound, so the use of water-based adhesive production safety, no damage to the health of the operator staff. With the increasing s...

After the composite product has been cured at a certain temperature and time, the interlayer peeling composite film adhesive layer still has a certain viscosity, that is, after the composite film peeling, the two-layer film will be re-glued together by hand, and the severe drying of the composite film adhesive layer will directly affect the peeling strength of the composite film, while the slight non drying phenomenon will lead to poor heat sealing strength after bagging, and the viscosity after the interlayer peeling. Heat sealing place is easy to wrinkle phenomenon, but storage a week or half a month later, packaging bag wrinkle phenomenon, this phenomenon, caused by the loss is often larger. Causes of non -drying composite film 1.The ratio provided by the glue manufacturer is not accurate, the proportion of curing agent is too small or the ratio of mixing glue liquid is misadjusted, and the curing agent is too little or ineffective. 2.In addition to dilute the solvent water or small molecular alcohol content is too high consumption of curing agent 3.Film moisture absorption, especially NY and cellophane, it is easy to appear not dry phenomenon. 4.The use of ink containing alcohol solvent does not volatilize completely resulting in the glue layer is not dry. 5.The use of polyurethane, polyester ink without hardening agent caused by the glue layer is not dry phenomenon. 6.The ambient temperature and humidity are too high, the prepared adhesive is placed for too long, resulting in the curing agent and water reaction for a long time. 7.Containing K coating PET film composite machine PET film additive influence. Corresponding solution 1.Generally speaking, the ratio provided by adhesive manufacturers is a reasonable ratio obtained through a large number of tests by adhesive manufacturers. Therefore, the ratio will not be inaccurate. If indeed because of the quality of the adhesive itself must be replaced by the adhesive; 2.Reduce the total content of water and alcohol in ethyl acetate (replace good quality ethyl acetate, the total content of water and alcohol is less than 0.2%); 3.When the composite moisture absorption NY and cellophane film adjust to improve the proportion of curing agent (5% ~ 10%), at the same time do not use damp film; 4.As far as possible to reduce the amount of residual solvent in printing ink; 5.The use of polyurethane ink: the first is to solve the composition of polyurethane ink dilution solvent, try to do not use alcohol dilution solvent. If alcohol diluent must be used when printing, it should also be done in printing to minimize the residual solvent; Secondly, if there is a printing film with white ink, finally, a small amount of hardener is added to white ink, which can increase the compound fastness. But added hardener ink use period is shorter, if there is surplus, and the interval time is longer in principle should not be used again. Finally, the purity of ethyl acetate used for preparing adhesive dilution should be...

Self-adhesive labels are ubiquitous in our daily life, and are necessary consumables for many manufacturers. However, the warping Angle of self-adhesive labels has been troubling many manufacturers. A small warping Angle will directly affect the beauty of the products, leading to their own products are not favored from the visual point of view. So, why will self-adhesive warping Angle? How to deal with this kind of Angle problem, here involves a lot of professional problems. The following Xiaobian to explain to you one by one. 1.When sticking self-adhesive labels on the automatic labeling machine, many manufacturers find that the warping Angle often appears, which is the initial viscosity problem, and the instantaneous adhesion is not strong. That is to say, when the roller of the automatic labeling machine presses the label on the bottle, the time is too fast, the pressure time between the label rubber surface and the bottle contact surface is not long enough, resulting in the label cannot be well adhered to the bottle, and it is easy to warpage. This is the case that the initial adhesion of the self-adhesive label is not strong. 2.Many people find that self-adhesive labels will fall off and lose viscosity after a short time. This situation is the problem of holding viscosity, is the retention of the poor. In other words, the durability of label glue is too poor. After reaching a certain period, the glue loses viscosity, has no adhesion and falls off naturally. It's the durability of the glue. The following is the specific treatment method of self-adhesive warping Angle: 1.The pressure of the press wheel of the labeling machine is not enough: adjust the press wheel of the labeling machine and check the machine failure. 2.glue viscosity is too weak: should choose the appropriate glue material; 3.Improper selection of adhesive: When selecting self-adhesive, first of all, we should determine whether the adhesive required by the self-adhesive label is permanent or detachable, whether it can be pasted once or re-pasted, and whether there are special requirements for the chemical characteristics of the adhesive for the self-adhesive label. For example, when labeling large curved surfaces (circular substrates less than 2 cm in diameter), instead of using thick or hard paper materials (such as mirror coated paper) as surface materials, thin or soft paper materials and adhesives with high initial viscosity should be used; For containers requiring hot filling, film materials and adhesives with good initial viscosity should be selected as the surface material of self-adhesive materials. 4, the coating tension control is not good: the correct label of the coating is smooth after being removed from the base paper, without curling. After labeling, the label can keep good follow-up; When the label with too tight film tension is removed from the base paper, the label will turn up, leading to the phenomenon that the edge of the label is easy to degummed, and the...

Adhesive label is a representative pressure sensitive adhesive product which coexists with adhesive tape for packaging. Its wide range of uses, such as: food, cosmetics, drugs and other use of senior beautiful label; Quality marking labels for fiber products, electronic machines, daily necessities, etc.; A price tag used in a supermarket or grocery store; Computer tags for schools, hospitals and offices; Industrial labels used in engineering management. It is widely used in all industries and fields. Its growth rate is increasing by about 15% a year. The substrates used are paper, polypropylene film, polyester film, PVC film, aluminum foil, fiber and so on. Pressure sensitive adhesive is divided into acrylic, rubber, hot melt and so on. Europe, the United States mostly used rubber system, and recently quickly transferred to the hot melt system. According to a person of insight, 80% of the future adhesive label to hot melt system. In Japan, it's almost always acrylic. Acrylic pressure sensitive adhesive, has outstanding weather resistance, but also has good cutting, this is the reason to occupy the market. In Japan, the sealing packaging machine is very common, so the requirements of label cutting quality, operation suitability is very strict. Paper adhesive labels almost all use acrylic emulsion pressure sensitive adhesive; Film adhesive labels use acrylic solvent pressure sensitive adhesive. Adhesive labels are roughly divided into permanent adhesion type, then peel type, frozen type. Permanent adhesive type is used on items that do not need to be uncovered once attached. Its physical properties require fast viscosity, adhesion, and cohesion can be lower. Repeel type must be attached once on the article, clean without leaving residue. So the requirement of its fast viscosity is good, but the adhesion force is low, and the cohesion requirements are high. The frozen type requires good low temperature characteristics due to the popularity of frozen food. They are more commonly manufactured by coating the isolation paper with pressure-sensitive adhesive, drying it and then recombining it with the substrate, and finally rolling it into the product.